Assuming you are talking about desktop
In the menu file>utilities> there is an option for Condense, you can try that, but Condense works about 60-70% of the time accurately. Print your present critical financial reports (inventory valuation, sales tax liability, a/r and a/p, P&L, balance sheet and any others you worry about), make a back up from the file menu and move it to another folder for safekeeping. Then do the condense, print the same reports - they MUST match or delete the condensed file and restore the original back up file
If condense, and period copy if you have the accountants version (same issues), do not work, the first two utilities on this page do work accurately
http://www.q2q.us/indexutilities.htm
I am not affiliated.